The use of boric acid and boron compounds such as borax and polyborates for the treatment of unseasoned wood is well known. For example, in New Zealand and Australia boron compounds such as borax and polyborates which are believed to convert to boric acid in wood, are used extensively to protect wood against insect and fungi attack. In general, these boron compounds are applied by dipping unseasoned wood into a tank containing an aqueous solution thereof and then storing the dipped wood for a period sufficient to allow diffusion of the boron compound into the wood. The solution is maintained in the dip tank at elevated temperatures and under constant agitation to prevent the boron compound from recrystallizing and settling out of the solution.
As can be implied from the above description of the use of borax and polyborates in the treatment of unseasoned woods, one problem associated with such use is the limited solubility of these boron compounds in water. Thus, when utilizing aqueous solutions of these boron compounds for dip-diffusion treatment of unseasoned woods it is necessary to maintain such aqueous solutions in the dip tank at elevated temperatures and under constant agitation. However, even under these conditions it is not possible to employ high concentrated solutions of these boron compounds and as a result, the amount of such compounds which can be dissolved in water and made available for diffusion into the wood during storage is severely limited. Thus, a need exists for new and improved boron compounds for use in dip-diffusion treatments for unseasoned woods and particularly for boron compounds which have a greater solubility in water at ambient temperatures than borax or the various known polyborates that have been employed.